Propeller



f' 'Y July 19, 1938. w. w. EVERTS 2,124,369 t l PROPELLER j Filed Feb. 4, 1957 .2 sheets-sheet 1v Gnou/uml I 'zo il v. gmc/XMI L30 wauferwz: 1f.

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Patented July 19, 1938 UNITEDl STATES PATENT OFFICE PnoPELLEn Application February 4, 1937, serial No. 124,129

7 Claims.

My invention relates to propellers.

An important object of the invention is to provide a propeller for operation within a fluid, such as a gas or liquid, whereby the propeller may be advantageously use d in connection with aircrafts, boats including surface ships or submarines, and fans used for Ventilating purposes or the like.

A further object of the invention is to provide a propeller of the above mentioned character, which is automatically actuated by-centrifugal force, to vary its pitch, as the pressure of the fluid` medium within which its operating varies at any given speed of rotation.

A further object of the invention is to provide a propeller of the above mentioned character,

having opposed centrifugally balanced "portions,

' for reducing friction and permitting of the free turning movement of the propeller blade upon its axis for varying its pitch.

A further object of the invention is to provide a propeller of the above mentioned character so constructed that the iiuid or air load acting upon the same is opposed by the action of centrifugal force, these two forces balancing each other to find the correct angle of the propeller, to eliminate vibration and bending moments and gyroscopic forces.

A further object of the invention is to provide a propeller of the above mentioned character embodying a single blade, whereby the propeller may be driven at an increased maximum speed with efliciency.

A further object ofthe invention is to provide strong and simple means for assembling the various parts of the device, for effecting a strong union, and permitting of the proper Vaccess of parts when desired.

In the accompanying drawings forming a part of thisapplication and in which like numerals are employed to designate like parts throughoutv the same,4

Figure 1 is a perspective view of a propeller embodying my invention,

Figure 2 is a front elevation of the propeller, upon an enlarged scale, parts being broken away,

Figure 3 is a longitudinal section taken on line 3 3 of Figure 2,

Figure 4 is a transverse section taken on line l-4` of Figure Figure 5 is asimilar view taken on line 5 5 of Figure 3,

Figure 6 is a side elevation of the propeller with the bearing device removed,

Figure '7 is an exploded perspective view of the bearing device,

lmy invention, the numeral (ci. 11o-162) Figure 8 is an assembled perspective view of the inner bearing unit of the bearing device, Figure y9 is an end elevation of the propeller showing the blade at the minimum pitch,

Figure 10 is a similar view showing the blade 5 at the maximum pitch, and,

Figure 11 is a similar view showing the blade swung past the maximum driving pitch position.

In the drawings, wherein for the purpose of illustration is shown a preferred embodiment of 10 I0 designates the blade of the propeller, which propeller may beV formed of suitable material, such as aluminum, an aluminum alloy, bakelite, wood or the like.

. The propeller is preferably formed integral and 15 comprises a hub portion II, carrying a shank I2 upon one side which is integral with the hub and blade I0. The hub also has a counterweight shank or member I3 integral therewith, arranged opposite the shank I2. The hub II projects upon 20 opposite sides radially beyond the shanksl I2 and I3, in the direction of the plane of rotation of the propeller. It might be stated at this point that the action of centrifugal force upon the blade I0 and shank I2 is balanced by the action 25 of centrifugal force upon the 4counterweight shank or member I3, these forces of course operating in opposite directions. This reduces friction upon the engaging parts and permits of the proper movements .of the propeller, to'be de- 30 scribed.

As more clearly shown in Figure 6, .the hub II is provided with an opening I4, having opposed cylindrically curved walls I 5, oppositely arranged,

and opposed radial extensions I6, having side walls I 6' and end walls I1.

The numeral I8 designates a propeller ordriving shaft, upon which is rigidly mounted a sleeve I9, for rotation therewith. This sleeve carries opposed pivot elements 20, preferably in the form 40 of tubular stub-shafts. These stub-shafts are radial with respect to the driving shaft I8. The numeral 2I designates an inner bearing unit as a whole, comprising semi-cylindrical bearing elements 22, having reduced innertting edges 23,

as shown. 'I'hese inner bearing elements 22, when assembled, produce a tubular structure, having segmented flanges 24, slidably receiving the sleeve I9 and positioned upon opposite sides of the stub-shafts 20, as shown. Formed integral with the bearing elements 22 are enlargements, Webs, or lugs 25, having straight parallel side faces\26, and cylindrically curved oppositely arranged faces 2'I. The webs 25 are provided with oppositely arranged cylindrical radial openings recesses include curved tops 3i and straight side walls 32, as shown. The cuter bearing elements-"i or blocks 29 have grooves or notches 33 at their radially outer sides. `The outer blocks or b'ea'r-A ings are longer than the widthiofthebubi'i I, and are adapted to project beyond same;;.-asfj;showii.

The outer bearings or blocks 29 are placed uponk the webs 26, and the entire.assembledpearlng, unit is then inserted into the'openingil of hub II of the propeller.

Adapted to be arranlg-ed.upon the oppositeface ofiheemagged mib lliardis'cs si, which-v mehr?,l cular, and are clamped tof' the 'hubI Ij by bolts 35" orth'e like.. These ,discs haveiopenings Y VSii formed therein, yoorr'e'sporiding to the .Shape jof the jfoplenings M" Theopenings 36 havegoppositelyfarranged curved walls 31,adapte`d to "coincide with the curved walls I5 of the opening I4 and sides asjtqcoiacide with the 'sides is', and. end walls' 39'V winch'. are arranged slightly inwardly of the endjwalls II.` The end walls 39 engage-.within the notches `orA grooves 33," while 'the side walls 32 ofthe outer bearing'elements or blocks 29 snugly engagethe s ide walls` 38 and also 'the side walls I6. j` The sleeve I9 is Ispacedfrom the inner wall of the jinner tubular bearing, unit 2|, vand 4this permits" of theturning ofthe propeller, upon its axisj" i0,`to"vary itspitch; 'The centers of theA pivotsforstub-shaftfs 2liV arejin alignment with the" `linelll of ther propeller blade when the propeller blade is injthe true 'radial position; In addition to theturning movement ofthe propeller Aupon its longitudinal axis about the longitudinal line Ill', theV propeller blade isl adapted to be turned lupon its transverse axisl about the center of the cylindrically curved fa'ce 2l of `the innerf bearing unit. `The`propeller .is therefore adapted to be turned upon its`transverse axis in a direction longitudinally of the drive shaft I8.Y By virtue of `this turning movement, the air load which is opposed by the action of centrifugal force, tends/t0.

swing .the propeller forwardly in a direction longitudinallyy of the drive shaft, which action is balanced bythe action'of centrifugal `force tending to return the propeller to the true radialrposition with respect to the drive shaft. .These two` forces willtherefore automatically ndfthe correct angleof .the propeller, withrespect to the longitudinal. axis lof the drive shaft, to thereby eliminate vibration of the propeller, bending moment and gyros'copicforces.. y

.When the propelleris rotating at,y sea level, as applied toy an aeroplane or thelike, and in lthe directionof the arrow, wherethe pressure of the atmosphere is. at the maximum, the propeller Lhas themi'nimum pitch, regardless of variations of.

speedQlfThe radial axis of thecentrifugally operated portion .or` hub A I 3 is inclined or disposed-at an ..acute angle withrespect'to the working face of the propeller blade..v lThe position o f the blade I0 (at ,thisminimum pitch is shown in Figure `9 and` also'fthepositiorlv ofv the `enlarged hub portion I,I-,.the walls ofthe sleeve I9nowengaging.

If the rotating propeller risesto peller blade. a higher altitude, the resistance of the air upon the unbalanced areas of thefblade decreases. v

The trailing area Ia of the blade is greater than the leading area lia and these surfaces are unbalanced so that the action of the air pressure thereon tends to turn the propeller upon its axis I0 to reduce its pitch. The action oi' centrifugal force upfn ltheadially,inlaged portion vfor hub I Ilisnovi sfdci'ent-,to canse jthisenlarg'e iportion to ,overcome this air pressure action and to turn r^theffpropeller upon the pivots or stub-shafts 20 Piiirlirection to increase the pitch of the propellrf Figure 10 shows the centrifugally oper- 'ted hubpo'rti'o'n =I Iiat`the true radial position at propelling" "pitchff/When the resistance of the airexceeds thehdrlvingaction of the propeller, as when making a power drive, the pressure upon ll the-traillig area I6a, which is greater than the leading area I5q,.fwill,:.serveto,overcome the actlonofcentrifug or'ce ,uporilthe .L radially Venlarged cel'itrifugallyy operated ,portion ofl huby .I I

extremefpositiori as `"shown,in Figure 11p/which is limited by nie jritactfof thewaus or the sleeve' I9 with'theIendjS. of fthe inner-'bearing unit 2I',. thereby further increasingfthe pitch "of the `propeller'l blade @beyond .the .maximum propelling pitcnf' i `When the aeroplane is in aknose dive, with the engine idling,` or dead,r the air pressurey acting upon the propeller 'will tend'to swing the same upon its transverse axis abouty the cylindrical surface 21,. which' action is opposed by that of centrifugal forcervbut :this rearward swinging movement-will relieve the propeller` ofstrains, to

a considerable extent,l and will ,prevent rattling.

A further advantage `of my propeller is` that it has Vonly a single blade and may therefore be driven Iat an rincreased maximum speed,4 with efiiciencyigAs is well,v known, when` a,.two or three. blade propeller is driven beyond about.

seventeen to nineteen hundred R.` P. M., the

efficiency,v of the., propeller is reduced, due Atothe factthat one blade movesinto the space or hole in the air produced by the leading blade. By

' having only one blade, properly balanced, this. disadvantage is overcome,`and my one blade propeller may be driven ata speed considerably above the normalemciency speedy of a two or three blade propeller',` with eillciency, thus allowing engine tobefdriven at its maximum eilciency speed. Y i

It isltojbefunderstood that the form of my invention herein nshown and described is to be taken y,

as -a.preferred.,example of thesame and Athe whieh'atimegthe bladell! will have the maximum various changesin the shape-size, and arrange-3,

ment offparts, maybe `resortedtmwithout ,depart-1 ing from the spirit of my invention or therscope of the subjoined claims.

Having thus described my inventiomfwhaflfl;

claimand desire to protect by Letters Patent'is: '1 l .L1A-propeller comprisingan elongated rotary.-

element," a. bearing device mounted uponf'the elongated rotary element to rotate therewithJ and turn upon an axis radially of the rotary element,

a second bearing device mounted upon theiirstA named bearing device and capable of swingingfin a direction longitudinally of the rotary element` I andpositively turning with the first named bearing device, and a, single blade propellerzmounted embodying a blade having unbalanced areas ar- 70 rotation'of the propeller, said recesses receiving tudinal axis of the yblade and having a centri!- ugall'y operated portion adapted to turn the blade upon its longitudinal axis when the pressure upon the blade varies at any given'speed of rotation, theilrst and second named bearing dvices serving to rotate the propeller, and means to substantially balance the radial thrust of the propeller. f

bearing device mounted upon the rotary element for rotation therewith and capable of swinging ated portion disposed generally at an acute angle with respect to the working face of the blade, the arrangement being such that the pitch of the blade varies as the pressure varies upon the blade when the blade is being rotated at any given speed.

3. A propeller comprising a rotary element, a bearing device mounted upon the rotary element, pivot means between the rotary element and bearing device and disposed radially of the rotary element, a companion bearing device mounted upon the iirst named bearing device to rotate therewith and capable of turning upon the bearing device in a direction at a right angle to the plane vof rotation of the rotary element, the companion bearing device rotating with the iirst named bearing device, and a single blade propeller comprising a blade having unbalanced areas arranged forwardly and rearwardly of the longitudinal axis of the blade and alcentrifugally actuated hub extended laterally in the plane of rotation of the propeller, the hub being arranged at an inclined angle with relation to the working face of the blade, the hub being iixedly secured to the second named bearing device, the first and second named bearing devices serving to rotate thepropeller.

4. A propeller comprising a rotary element, substantially radial pivots carried thereby, a bearing unit mounted upon the rotary element and havingl substantially radial openings to pivot--l ally receive the pivots, said bearing unit embodying webs having cylindrically curved faces extending in a direction at substantially a right angle to the axis of rotation of the rotary element, a single blade propeller element including a blade and a centrlfugally operated hub arranged at an inclined angle with respect to the working face. of

the blade, the working face of the blade having ,l

unbalanced areas arranged forwardly and rearwardly of the longitudinal axis of the blade, the hub having an opening formed therein, and bearing blocks iixedly mounted within such opening and having cylindrically curved recesses extending in a direction at a right angle to the plane of 2. A propeller comprising a rotary element. a

ma wel.l the bearing una and blocks serving to' j rotate the propeller.

5. A propeller comprising a rotary element,

bearing means mounted upon the rotary element. and including opposed webs, the webs l having .outer curved faces extending `lomi'itudinally of'v the longitudinal axis of the rotary element to pro-- vide a pivot element having its turning axis disposed at a right angle to the axis of rotation of the rotary element, a propeller element including a blade and hub,l said hub having an opening formed therein, bearing blocks arranged within the opening and having recesses to receive the webs, said recesses having outer curved walls extending longitudinally of the longitudinal axis of the vrotary element, the bearing blocks turning about the turning axis of the pivot element formed by the webs, elements secured to the opposite sides of the hub to retain the bearing blocks within the opening of the hub, pivot means for mounting the websupon the rotary element. the

pivot means having its longitudinal axis arranged at a lright angle to the axis of rotation of the rotary element and at a right angle to the turning axis of the pivot element formed by the webs.

means for causing thepropeller element to'turn` upon its longitudinal axis about the pivot means to vary its pitch, and means to substantially balance the radial thrust of the propeller.

6. A propeller comprising a rotary element, oppositely arranged radially projecting webs, said webs having outer curved faces extending longitudinally o f the rotary element, the curved faces providing a pivot element having its turning axis at a right angle to the axis of rotation of the rotary element, a propeller element including a blade and hub, said hub having an opening pro.- vided with opposed recesses to receive the webs, said recesses having outer curved faces extending longitudinally, of the longitudinal axis of the rotary element and engaging the curved faces of the webs, the recesses having side walls to engage with the side walls of the webs so that vthe webs rotate the propeller, pivot .means )for mounting the webs upon the rotary element, the pivot means having its turning axis disposed at a right angle to the axis of rotation of the rotary' part to turn the blade upon ,its longitudinal axis,

and bearing means to mount the blade upon the rotary element, said bearing means including a pivot element having its longitudinal axis disposed at a right angle to the longitudinal axis of the blade so that the blade may turn thereon and find its plane of rotation and a second, pivot element having its longitudinal axis arranged at a right angle to the longitudinal axis of the iirst pivot element and also extending longitudinally of the longitudinal axis of the blade so that the blade may tum upon its longitudinal axis to vary its pitch.

WALTER W. EVERTS. 

